The Knierims are the only US pair I have gravitated towards in many years and are the US's clear top pair, despite the issues they've faced. Their pair element ability is comparable to any international pair, which I've never said before about a US team. Alexa is one of the best female pair skaters in the world; her natural athleticism is off the charts and helps their twist & throws to be special. She just needs continued guidance and encouragement in the harsh world of US pair skating, where people expect pairs to get unrealistic/immediate results because of the US's rich history in the other disciplines. The Knierims have made great improvements this year in PCS, programs, packaging. They took risks and tried many new things (some worked, some didn't) in order to develop aspects of their skating that puts them in a better position against strong international competition, which I hope the US recognizes.
The Knierims remind me a bit of Tarasova/Morozov in terms of physical stature, long lines, athleticism. They're a potential top 5 at Worlds and would have the easiest time among US pairs at finishing top 10 this year. Given their recent scores, they could do it even without jumps assuming the rest of their big elements are fine. Despite changing coaches/countries at a strange time and looking a bit lost earlier in the season, they have the highest average US pairs score this year. I expect them to continue to get better now that they're settled into a comfortable training environment. They're our safest bet at Worlds, and our only chance at a great finish (assuming the event is a good one).
Kayne/O'Shea have a ceiling but are probably our #2 pair. Their programs are set up to do well more so domestically than internationally, and I'm concerned they will win Nationals. They have a well-choreographed LP to a warhorse that a casual US audience will fall for (I much prefer the Knierims' LP), but they're doing less technically and have quality issues. They don't do throw 3Lutz in either program anymore, and in the SP they're only doing a throw 3Sal, a small one at that. They could finish top 10 at Worlds--the field isn't as strong this year-- but they have equally as good of a chance of not getting top 10. Their scores are often in the 170s or 160s, which won't be enough. 3 of their 4 SP scores this season have been in the 50s (the other was 63 without a fall), which is an issue that has plagued them throughout their career and puts them at constant risk of finishing very low in the SP and far from the final groups. They have trouble with this year's required death spiral, and the quality of their twist and throws doesn't stack up against better competition. They had one solid total score which makes me rank them ahead of C/L, but their scores have been all over the place.
Cain/LeDuc talk very positively, but they haven't had an easy time scoring points. They sell their programs well, and they're probably at their best while doing choreography. While terrible lift falls won't happen often, they're at greater risk of a major mishap than other pairs because she's truthfully outgrown the discipline. They've had trouble on that lift before, as well as shaky moments on other lifts. They don't do a reverse lasso lift like all the other pairs (the big point getter), and they routinely miss levels. Their throws are always eked out and they've had jump under-rotations at every event. Their twist has gotten better, but it's erratic and I don't see them getting over a certain hump.
Denney/Frazier have strong lifts, but they've had a lot of trouble generating decent scores the past couple years. Their TES tends to be low, and they've withdrawn from events. I believe they could be stronger than Stellato/Bartholomay and maybe C/L and K/O, but they can't give away so many points or have URs every time. Stellato/Bartholomay got a big SP score at Nationals last season, but it wasn't the type of score they could get internationally. Some of her moves are lovely to watch but it's been hard for them to get past a certain point.
There have been so few US scores over 180 pts this season (the Knierims are the only team that has done it multiple times), and if you don't score in the 180s relatively easily, then a top 10 finish at this Worlds isn't a good bet, especially under the unique pressure of being the only US pair there. None of our pairs have been in a situation like this except the Knierims, who delivered in 2017. Their fluke death spiral fall wrecked their program in 2018, but I think Alexa would be in a better place mentally this year since they'd be going into Worlds knowing they're the only US pair instead of dealing with the negativity & panic that ensues when the second US pair doesn't qualify for the LP again. In most instances, the Knierims should win Nationals, but I'd feel more hopeful if it was scored like an international event. A concern is that some US pairs tend to have their best skates at Nationals and that the scoring gets a little haywire in part based on crowd response and standing ovations that would be absent at an international. I hope our pair with the strongest scoring potential on the world level is sent.
..... who is imaginative enough, and off-the-wall enough, to help them create some gorgeous, innovative lifts that would carry them in a different direction. Something where the height of their lifts didn't matter so much, and something that would really be unique to them. 
They've moved back to Florida to work with John Zimmerman, I don't know if that rules out working with Marina. 
